Method of and apparatus for obtaining ion concentration effects



Nov. 2o, w3. E. A. KEELER METHOD oF AND APPARATUS Foa QBTAINTNG ToNcoNcENTRATToN EFFECTS Filed May 1, 1922 s i f, I i i glllllllllllllll'fll"I" INVENTOR.

(2m d. 'AMM BY 4 ATTORNEY.

Patented Nov. 20, 1923.

lnarran STATE PATENT OFFICE-.

EARL A. KEELER, O'E NORRISTOWN, PENNSYLVANIA, AssIGNOR To LEEDS a NORTIIRP COMPANY, 'OE PHILADELPHIA, PENNSYLVANIA, A CORPORATION OE PENNSYL- VANIA.

METHOD OE AND APPARATUS EoR OBTAI'NING ION CONCENTRATION EFFECTS.

Application led May 1,

and useful Improvements in Methods of and Apparatus for Obtaining'lon Concentration Effects, of which the following is a specification.

My invention ,relates to-a method ot and apparatus for' obtaining electrical effects by the vco-action ofelectrodes with an elec# the mixture of electrolyte and gas flows in a stream past and in VContact with the electrode.

-Further 1n accordance Wlth my Invention,

either the gas ,or electrolyte solution is em-- ployed as a motive Huid for entraining the other or operating upon it upon the prin- Veiple of aspiration, to cause their mixture in a stream which passesand contacts with the electrode.

Further in accordance with my invention, air is employed as the gas or gas electrode, in the utilization or determination of' ion concentration, as degrees of alkalinity or acidity; and it is a feature of my invention that air is so employed as a gas in relationswhere formerly hydrogen was commonly employed, the utilizationof air'in many relations saving the expense and mconvenience of providing a source of h 'ydrojf'` gen or other gas. A l My invention resides in the method and structure hereinafter described and claimed. For an illustrationy of one of numerous forms my invention may take, reference. is to be lhad to the accompanying drawings, in which:

Fig. 1 is a vertical sectional View, partlv 1922. 'serial No. 557,597.

vention and utilizable in practicing my method.

Fig. 2- is a section on thefline 2 2 of Fig. 1. i

Fig, of is a generic representation of apparatus for producing a desired gas by electrolysis.

Fig. 4 is a graphic representation of relations between potential differences and ion,

concentration as regardsvehanges of alkalinity andacldity when a hydrogen electrode is employed.

Fig. 5 is a similar characteristic relating to the employment of an airelectrode under similar circumstances. j

Fig. 6 is a diagrammaticl view of one of many modes of utilizing vmy apparatus, together with means for compensating or correcting for change in nature of lgas for the gas electrode.

Referring` to Figs. 1 and 2,71 is a block or mass of insulating material of any suitable nature, as hardrubber, fmolded condensite, bakelite or the like. Within -it are formed the passages 2 and 3 between which is disposed a barrier or battle, 4 in.an enlargement Or chamber 5 which communicates with the threaded aperture (i into which is threaded the tube or nipple 7 of insulating material, and upon which is threaded the member 8, preferably of insulating material, and having thclapciture 9. Between the ange of the member 8 and the end of thctube 7 is clamped a perforated or gauze electrode 10 of platinum or any other suitable material., A platinum or other suit able conductor or wire 11 connects with the electrode 10 `and extends through a hole 12 in the block l'to the exterior thereof, Where it connects with the binding post 13 carried by the block 1. i

' ,Within the tube 7 is disposed in register with the baille 4 the barrier or baiiie plate 14, preferably terminating. short of the electrode 10. Upon the clamping cap 8 fits the circular cap member 15, cut away at 16 so that 'the interior of the cap is Open to the atmosphere, the cap structure 15 forming in effect a dam over whose edge 16 electrolyte may lowas hereinafter described. The cap V is'retainedin position by the'springclamp 17, pivoted upon a screw 18 carried by the block' 1. By swinging the clamp 17 to one 'side the cap 15 maybe removed and thereafter'the cap or clamping member 8, allowing access to or removal of the electrode 10,

. for afterremoval of the electrodel() allow-4 ing removal ofthe baille or barrier plate 14,

'Communicating' with the passage 2 is the discharge pipe -19 oflan aspirator A, of any suitable or convenient form,4 The aspirator is here indicated' generically as comprising the nozzle's'tructure 20 projecting into the suction chamber 21, with which comm-uni.-

- chamber 25, if filtration is suitable or de sirable. The electrolyte then passes through the nozzle 20 and entraine air or other gas entering the suctionchamber 2 1 through the vpipe 22, and the mixture of electrolyte and gas passes downwardly through the pipe 19 into the passage'2' around the baflies 44,14 into contactwit-h the electrode 10, thence into the chamber 3, Aand is dis? charged through the discharge pipe 26.'

Some of the electrolyte passes through the electrode 10 into the dam formed -by the:

cap 15, which standsl in the dam or overflows its edge 16, according to therapidity of flow of themixture of electrolyte and gas, the overiow edge -16 preferably being vsomewhat higher than the uppermost limit ofthe aperture 9 in .the member', whereby 'the entire electrode 10 will be in efect subconcentration involved.

Any suitable source of such'gas may bel merged'in the stream of electrolyte and'gas,

the structure described affording means for bringing the Agas effectively into contact with both sides of the electrode 10.

While I have described air as `tl1e 'gasentering 'through the suction pipe 20 into mixture withthe electrolyte delivered by the nozzle 20, it will be understood that any other gasmay be employed, as hydrogen,

chlorine, or any gas` suitable to the natu-re of the determinations orv utilization of ion provided, as, for example, a tank of gas under pressure and connected' throughthe needle orth-rottling valve to thepipe 22.'

Where it is desired, however,l to produce theggasat. the place. of. consumption, apparatussuch as shown in Fig. 3- may be employed, whereof G is a direct current generator connected -to' the platinum or other I j suitable electrodes 27v and 28 immersed in suitableelectrolyte in .the container 29..; H

hydrogen gas desircd,the electrolyte may be ,acidulated water, and the direction. of current between the electrodes 27 and 28 is 1 s 'uch that hydrogen is liberated at the elec-v trode 28 within the bell 30, from which it-A passes off through the tube 3 1, which may be connected to the aspirator' suction tube 22.. In case oxygen is" required, the. direction'- of current between electrodes' 27 and 28 may Abe reversed, in which case oxygen will be ,generated at electrode 28 and delivered to 4the tube 21 at4 aspirator A;

for chemical or other processes or for boiler feed purposes, air may to great advantage.

be'employedas the gas for mixture with the water or electrolyte to contact with the ele'cf trode 10. However, in such an. industrial plant hydrogen or other gas, if preferred',

In industrial-plants, Where the electrolytel I 'delivered through the pipe 23 is raw or' other water .to be' utilized within. the plant may be, cheaply produced without recourse f to a tankof: hydrogen or other .as under. lpressure," byapparatus such as in icated in ig. 3, the generator Gr .of which may be power about the plant, the amount of power required for the production of hydrogenor other .gas being relativelyinconsequential.

While I have describedthe employment of a liquid4 or electrolyte solution as passing through the nozzle structure '20 of the electrode v10 may be delivered through the -nozzle structure 20 under suitable pressure,

readily driven by any suitable source of aspirator A, it' will be understood that the gas to be lbrought into contact lwith the in which case the electrolytewill be drawn ,in through the tubev 2 2 and entrained by the Agas jet and mixed therewith, with the result as before, to Wit, a-streamfconsisting of a mixture of gas and electrolyte 'passing in Contact with the electrode 10.

'fluid of the aspirator, and either the gas or electrolyte may be the materialentrained. Only the gas electrode has thus far been described; .the other electrode, .generally a calomelelectrod'eior half cell, may be provided in any suitable way. In the example illustrated, the block 1 is provided vwith a chamber o r passage 32 accessible upon re' I Iroval of the threaded plug 33, preferably chamber 321s disposed the grid 35, for example, of platinum wire gauze having applied thereto a suitable paste coninedlby .l i

a wrapping o r bag 36 of silk or other suitable fabric or p'ervious material. Connected tothe' grid 35 is the platinum or otherj suitable conductor 37 extending through' a` Ahole. in the block 1 and connected to the' binding Vpost 38. A'. passage 39 connects the chamber 5 with the c berl 32. This-passage is preferably of' capillary or small d- It'will therefore be understood that either Y the electrolyte or the gas' maybe themotive provided 4with a gasket 34; within the loc I example, a tenth normal solution of potassium chloride, is delivered from the storage.

ameter, for enample, of the'crderof twov one-hundredths of an inch, though it will b e understood that an other suitable diameter may` be employe lith the chamber 32 communicates the pipe 40, to which a suitable solution. as, for

vessel 41 `throughfthe flexible tube 42 controlled by. the pinch cock 43. p

The solution from the reservoir 4l passes into the chamber 32 into contact with the grid 35. and its paste, and flows in small quantities through the passagel39 into the chamber 5 into miXtureiwith-the electrolyte flowing through the passagesand 3.

There is accordingly formed a primary cell one of whose electrodes is the gas electrode 10, and whose other electrode is the paste or a component thereof held by the grid 35.

, be of platinum or gold, and is usually covered* with platinum black or the black of iridium, palladium or the like.` When hydrogen ion concentration is involved, hydrogen gas may be delivered in mixture with the electrolyte, or, as aforesaid, and preferably under certain conditions, ordinary air is employed in place of hydrogen. 'When the concentration of other than hydrogen ionsis involved, the' negative electrode 10, instead of being a hydrogen or air electrode, will be suitably different.. For example, if

' concentration of chlorine ions is involved,

chlorine gas may be delivered iii mixturel with the electrolyte.

' It will therefore be understood that my invention is not limited, as to either the positive. or negative electrode, to the particular materials described, it being Within the skill of the art to vary the coatings, fluids, liquids aiid gases employed to adapt the electrode structures to the particular conditions or circumstances under which they are to be em iloyed.

y the method and apparatus described,

the amount of gas brought into contact with the electrode l0 varies with rate of flow of the electrolyte through the pipe 19 and passige 2, an increase of rate or flou' bringing within a certain time -greater quantities of gas into contact with the electrode 10. In this respect. my apparatus and method are distinguished from prior practice wherein -a movement or current of they electrolyte vtends to carry the gas away from the electrode and thereby decrease the effectiveness of the gas electrode. Furthermore, by my methodand apparatus, all of the gas is applied at the surface of the electrode, thereby lreducing the gasconsuniption, which. makes it possible'to employ a small electrolytic generator to produce the gas, as described in connection with F ig. 3.v My method and apparatus are particularly adaptable to the continuous measurement or utilizationof Variations in the ion concentration of flowing solutions or electrolytes. For example, the electrolyte may be the water of. a municipal `or industrial supply; by connecting the aspirator A to a faucet or pipe traversed by the Water'supply, and entrain-` ingair or other suitable gas through the pipe 22, the complete cell Will continuously produce and electro-motive-force Whose magnitude varies with changes in magnitude of ion concentration in the electrolyte, and this varying electro-motiVe-force may be continuously or intermittently measured, or continuously recorded; or such varying electromotive-force may be employed, .as through the instrumentality of the hereinafter described galvanometei'., tocontrol any suitable control apparatus, as, for example, such apparatus as described in ni'y prior application Serial No. 37 4,267, filed April 16, 1920. Referring to Fig. 6, a simple potentiometer arrangementA is indicated for employ'- ment of the celll described. In circuit With the battery B is a resistance R, in shunt. to

va variable portion of which are connected the galvanometer K and the cell. For example,`the bindin post-13 may be connected through the a Vanometer K to thev rider or contract 44 s idablealong the resistance R and over the scale S, which may be calibrated in any suitable units, as those of ion concentration, PH value, acidity, alkalinity, electro-niotive-force, etc. The binding post 38, for the simplest case, will be connected directly to one terminal of the resistance R "by ommission ofthe resistance R1 and battery B1. For example,if measurements of determinations ofy hydrogen ion concentrations are involved and'hydrogen gas 1s employed with the electrode 10, the scale S may' be read directly in terms of PH values or hydrogen -ion concentrations, the scale S being determined from the characteristic of Fig'. 4, in which ordinates are potential differences and abscissae ion concentrations, when a hydrogen electrode is employed. The contact. 44 is moved alongthe resistance Rl to such position that the deflection of the galvanometer K is nil; the correct reading then appears directly beneath the contact 44 upon the scale S.

In Fig. 5 is indicated a characteristic similar to .that of Fig. 4, where, however, air

is employed in lieu of hydrogen.- The elecvfor example, suitable correction may be in# troduced forthe employment ofy air by connecting atany suitable point in the circuit ofthe galvanometer K the resistance R1 travling the mixture through an electrode.

tinuously flowing vthe mixture in contact Y f z K trolyte, of a gas/generator', an aspirator for 4ersed by current'from' the battery B1, .the

magnitude of theresistancel R1 included in the galvanometer circuit being so chosen that the fall of potential across such portion of the resistance R1 suitably corrects or compensates orthechange fromk hydrogen gas to air. Whilethe amount of the resistance R1 in'thegalvanometer circuit is .'shown as Variable, it will `be understood that it may oe fixed after having once been properly determined.

In determining the acidity of water, the

.employment of air in mixture with water has provedv satisfactory, the air apparently behaving as an oxygenelectrode.

While l haveireferred to the employment .of a'single gas mixture with the electrolyte, it will be understood that amixture of gases in mixture with the electrolyte may be employed; and that of the mixture of gases,

one or more of them may be neutral in the sense thatfit is ineffective as regards rthe electro-motive-force produced by the elec-` trodes or primary cell. For example, in employingair there'is in fact .employed a m1xture of oxygen-with nitrogen, oxygen4 being the active or effective gas while n1' What I claimis: A 1. |he method of maintaining a gas electrode for. producing an efectjdependent upon the concentration of an ion of an electrolyte, which consists in mixing with the electrolyte the concentration of an ion whereof is involved a gas suited to the ion whosevconcentration is involved, andpassing. the mixture in contact with an electrode.

2. The method of maintaining a gas electrode for producing an effect dependent upon the concentration of -an Vion of an electrolyte, which consistsin mixingwith the electrolyte the concentration Y of .an ion whereof is-A involved a gas suited to the ion whose concentration is involved,v and controgen' is merely neutral vand a diluen't.'

with a solid electrode; i l

3. The methodof maintaining valgas electrode for producing an effect dependent upon the concentration of an ion of an .elec-- trolyte, which consists fin mixing with the electrolyte the concentration of' .an ion whereof is'linvolved a gas suited to` the ion whose concentratlon 1s involved, and {low} maratea 4. The method ofmaintaining a' gas elec-i trode for producing aneEect dependent uponJthe concentration'of an ioni of an electrolyte, which consists in mixing-with the electrolyte the" concentration -v ofl an ion whereof 'is involved a gassuited to the ion whose concentration is involved' and -a diluting gas,and passing themixturefin contact with an electrode.

6. The method of` eifectingcontact.' be# tween' an electrode and gas and 'an elec- Itrolyte, which consists in employing the elec` trolyte as a motive fluid,'entra1ning the gas thereby, and passing the mixturel in con-v tact with the electrode. f.

7. The method of effecting Contact between an electrode, 'gasand an electrolyte, -which' consistsin generating the gas, utilizin'g the electrolyte as a motive fluid to entrain the gas as it is generated, .-and passing .the mixture in contact with the electrode.

8. 'Gas electrode structure comprising an' electrode, and means 'forpassing in contact lwith said electrode a mixture- 'of electrolyte and gas.

'electrolyte in', contact with said electrode, c and means 4for introducing gas into the elec# trolyte current. 10..Gas ,electrode structure comprising sourcesv of gas'and electrolyte, an aspiratorl employing one of them as motivefluid and entraining the other, and an electrode disposed in the discharge of said-aspirator.

-9. Gas electrode structure comprising an electrode, means for producing a current of i 11. Gas electrode structure comprisinga l,source of electrolyte under pressure, an

aspirator employing sai-d electrolyte as mof tive fluid, v means delivering gas into'said aspirator for mixture with said' electrolyte, and an electrode inthe discharge 'from said aspirator.

12. Apparatus for maintaining a gas elec-' trode comprising agas generator, means for mixing .the gas as generated with anelectrolyte, an electrode, and means for .passing the mixture of4 gas and electrolyte in contact with said electrode. i n

13. -The combination with a source of elec- 'bringing the electrolyteand gas from said generator into 'mixture witheach other, and an electrode' disposedl in the `discharge of said 'as irator.

14. he combinationwith a source of elec' ,trolyte under pressure, of an aspirator em-y ploying said electrolyte as motive fluid, a gas generator connected with the suction ot said aspirator, and an electrode disposed `in the discharge from4 said aspirator.

15,. The combination with a source of elecf trolyte under pressure, of an aspirator employin said electrolyte as motive fluid, an electro ytic gas generator delivering gas to the suction of said aspirator, and an electrode disposed in the discharge of said aspirator. l

16. The combination with a member having a passage through which electrolyte and gas are conducted in mixture with each other, of a perforated electrode through which said mixture passes.

17. The combination with a member having a passage through which electrolyte and gas are conducted in mixture with each other of a perforated electrode one side of which is in communica-tion with said passage, and ka liquid-retaining dam on the opv posite side of said electrode.

forming member carried by said second member adjacent said electrode.

20. The combination with a member having a fluid passage, of a member forming a lateral passage, a perforated electrode disposed upon said second member, a damforming member carried by said second member adjacent said electrode, and baffle structure extending across said passage into said second named member.

21. The combination with a member having a fluidpassage, of a member forming a lateral passage, a perforated electrode disposed upon said second member, a damforming' member carried by said second member 'adjacent saidy electrode, and baiiie structure extending across said passage into said second named member, said baffle structure comprising registering'members one of which is disposed in said second member and removable therefrom.

22. The combination with a member having a assage for conducting a mixture vof electro yte and gas, an electrode with which said mixture contacts, a chamber in said member, a second electrode therein, and

fluid passa e connecting said first named passa e witIi said chamber.

23. he combination with a memberhaving a assage for conducting a mixture of electrolyte and gas, an electrode with Vwhich "said mixture contacts, a chamber in said member, -a second electrode therein, and a capillary passage connectingsaid first ynamed passage with said chamber.' y 24. The combinationlwit ing a plurality" of'chambers. a passage connecting said chambers, an electrode in one of said chambers, means forco-nductingfluid past said electrode through said passage into another of said chambers, and a gas elec-- trode in communication with said other chamber.

25. A gas electrode comprising the combination with an electrode, of means for mixing air and electrolyte, and means for passing the mixture in contact with said electrode. y

26. vA gas electrode comprising the combination with an electrode, of' means for mixing an electrolyte with oxygen diluted with another gas, and means for passing the mixture in contact with said electrode.

27. .In the art 'of determining or utilizing variations of ion concentration, the method which consists in mixing an electrolyte the ion concentration whereof is involved with a. gas, passing the mixture in contact with an electrode, and producing a difference of potential vbetween said electrode and a second electrode in contact with said electrolyte. i l

28. In the art of determining or utilizing variations of ion concentration, the method which consists in mixing an elech amember ,hav-

trolyte the ion concentration whereof is involved with air, passing the mixture of electrolyte and air incontact with an electrode,

4and producing a difference of potential between said electrode anda second electrode in contact with said electrolyte.

29. In the art of determining or utilizing variations -of ion concentration, the method which consists in mixing an electrolyte the ion concentration whereof is involved with air, passing the mixture of electrolyte and air in contact withan electrode, and producing a difference of potential between said electrode and a calomel electrode in contact with said electrolyte. t

30. The method of determining variations of ion concentration of a water supply, which consists in employing water from said sup'- ply as a motive fluid, entrainin thereby a gas, and continuously flowing t e mlxture in contact with an electrode, and producing a potential difference between said electrode and a second electrode co-acting with the water. I I

31. The method of determining variations of ion concentration of a water supply, which consists in employing water from said supply as a motive fluid, entraining thereby air, continuously flowing the mixture in contact with an electrode, and reducing a potential difference between said) electrode and a second electrode co-acting with the water.

-@ i M' mamme 3.2. The. combination with a; cell having a gas electrode, of a circuit with which said gas electrode, of a circuit with which said cell is related, a'n associated scale havcell is -related, andelectrical means in said ingv markings corresponding withA a ascircuit for compensatin for a change in the of predetermined character,` and means or 15 nature of the gas vof sai electr-ode. compensating said circuit for change to a 33. The combination with a cell having gas of dierent character. 'i a gaselectrode, 'of a` potentiometer circuit En testimony whereof I have hereunto with which said cell. is related, and means affixed my signature this 28. "f,day of April', for compensating said circuit for a change 1922. l 10 in the nature of the gas of said electrode. A

34:. The combination with a cell having' a i EARLA. KEELER. 

